A little tip on microSD cards.

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I have just gone through 4 sd cards, all of different brands, about to get my 5th so I figured I give a little insight on class ratings, cost and brands of microSD to help people deciding on which to buy.

The comparisons are among a Sandisk 16GB class 2, Sandisk 2GB class 2, PNY 4GB class 4 and RiDATA 16GB class 6.

Somewhat surprisingly, both of the Sandisks performed significantly better than the other 2 SD cards. My standard transfer rates to and from these were averaged at 4.5 to 5 MB/s, whereas the PNY was typically 2MB/s and the highest I saw was 3.2MB/s, while the RiDATA was actually the worst at consistent 1.9-2.2 MB/s. While the cheapies (PNY, RiDATA, Komputerbay, etc.) seem appealing at a sometimes lower price, they definitely do not perform anywhere near as well as Kingston and Sandisk, which seem to perform above and beyond their specs. Funny thing is I have been seeing the higher end sd cards from the cheap brands, like 16GB class 4 and up, being the same price as Kingston and Sandisk. I am about to receive my next SD, a Kinston 16GB class 4, and have seen nothing but great ratings on as well and is rated by consumers to have a consistent transfer rate of at least 6MB/s. I have also seen reviews on the Transcend SD cards having the same issues as these other low grade brands, but the reviews are definitely mixed because some people report having "quick transfer rates", but I have never used one of these so I cannot say for myself what is true of these.

But in my conclusion, unless you are getting a Sandisk or Kingston, you will be disappointed to find that the card you bought is definitely not even worth a class 2 rating most of the time.

I know some will probably say "Well so-and-so did a speed test on such-and-such card and it did well on it." Well, those do not apply to real world situations where someone is actually transferring differentiating amounts of data to/from the card so I couldn't give a crap about those anymore. I personally have used many SD cards and watched the transfer rates of each one, differing from transferring anywhere between 30MB to 10GB at a time and seen the same transfer rates in each of these cards.

So do not be swayed or fooled by the seductive price and "high rating" of the low brand microSDs, spend a couple extra dollars and get what you're paying for.

I use my class 2 16GB card from my old Droid 1. Flawless and great transfer speeds.

Great write up. I'm considering getting a 16 or even 32gb card. This helps a lot.

Thanks for the write up.

I currently have a SanDisk 4gb SDHC Flash Card. I am thinking about getting a 16gb card.

There's a deal on NewEgg.
http://www.newegg.com/Product/Produc...82E16820171386

Coupon Code: EMCZZYR26
Get's you 10% off, I believe.

Enjoy!


EDIT -- Better deal here.
http://www.amazon.com/SanDisk-microS.../dp/B001L1H0SC

I just bought me a Transcend 16gb class 6 microsd card and I gotta say the thing is blazing fast. Taking pictures is instant now instead of getting a slight lag I got with the stock 2gb class 2 card, also downloading file attachments is instantanious, before I would be stuck on the fetching attachment screen for what seemed like forever. I highly recommend this card to anyone looking to upgrade.

I am so glad to see this thread, I have been trying to do some detailed research on microsd card comparison lately, but its hard to find anything other than people saying "oh yeah this card is fast" etc, but no real detail. Now I got my new card and am having major problems with it.

I've been using an 8gb Sandisk class 6 for about a year or so, but needed a 16, so after much indecision, I decided on the Transcend 16gb Class 6 after reading some decent reviews on newegg. I received it today and immediately ran some benchmarks on it to compare to my Sandisk, and at first I was impressed.

Sandisk 8gb Class 6 microsd

Transcend 16gb Class 6 microsd

Even though the Sandisk was beating it on the small files, real world performance was great, until I put the Transcend into my phone. For some reason it drags my phone to a crawl, and if I do something that needs alot of access to the card, the phone will completely freeze and require a battery pull. I have tried formatting in the PC, formatting in the phone, I am at a loss and I don't know what the problem could be. It's so slow it can't even play music without skipping. Any ideas would be greatly appreciated.

I was reminded recently that HTC lags up write/read when the sd card is in the phone (bogs down the read-ahead speeds). Ziggy's kernels have a fix coded in to correct this. And with his current new release of kernels that run at stock speed with some light undervolt, I suggest everyone switch to his kernels.

Also, small file read/writes is a little slower on larger SD cards compared to smaller ones. Allocation unit size somewhat plays a role in this as well.

EDIT: I also recommend always formatting through PC and never with phone. The phone format option is defaulted at formatting in FAT rather than FAT32, which can cause issues (i.e. flashing PB31IMG.zip in hboot etc.). Plus you can control the format better on a computer anyways.

earthtodigi did you format the card to fat32? I have the exact same card and its running great, no slowdown at all.

Sent from my ADR6300 using XDA App

Yes I've formatted it FAT32 in the computer, and in the phone. Tried changing the allocation size as well. I plan to try ziggys kernel just to see, but I don't see why the stock kernel would cause such issues.

What's really weird is, I got two card speed test apps from the market, and on both of them, it outperforms my Sandisk card while in the phone. On one of the test though, it shows 14 Mb/sec write speed, but only 5 Mb/sec read speed, which I assume is the read-ahead issue reportedly fixed by the kernel.

One of the reviews on newegg for this card, the person says they had trouble getting their incredbible to recognise the card, but after they formatted it they had no issues.

I'll let ya know how the kernel goes here in a little bit.

+1 for Sandisk. I have their 16 GB Class 2 and it consistantly does 5 MB/s.